<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta
        name="viewport"
        content="width=device-width, initial-scale=1.0"
    >
    <title>AJAX 取消请求</title>
</head>

<body>
    <button>点击发送</button>
    <button>点击取消</button>
    <script>
        //获取元素对象
        const btns = document.querySelectorAll('button');
        let x = null;
        btns[0].onclick = function () {
            // const x = new XMLHttpRequest();
            x = new XMLHttpRequest();
            x.open('GET', 'http://127.0.0.1:8000/delay');
            x.send();

        }

        //abort （属于AJAX对象的一个方法）取消请求
        //这里的 x 用 let 而不用const 好好思考一下 
        btns[1].onclick = function () {
            x.abort();

        }
    </script>

</body>

</html>